Image-forming apparatus typically include an image-bearing photosensitive member, such as a drum, on which an image is formed as the drum is rotated past a developer member and subsequently transferred from the drum to a sheet of paper or the like. After the image is formed and transferred, any developer of toner remaining on the drum must be removed by a cleaning member. Such cleaning members are known in the art and generally include a housing enclosing a fixed elastic blade or brush to clean the developer off of the drum by a wiping or brushing action. The particles are normally recovered through an elongated aperture communicating into a lower chamber of the cleaner housing in which the blade or brush is mounted. The particles collected in the chamber are either stored therein and discarded along with the housing assembly or are collected and reused.
Wiper blades used in such cleaning devices generally have a flat surface which extends along the length of the drum, and as the drum rotates, the lower edge of the blade contacts the drum along a line on the surface of the drum along the length thereof.
The wiper blade of such cleaning devices generally is made of rubber or a flexible plastic material and is usually rigidly and permanently mounted to the housing and extends therefrom for contact with the surface of the photosensitive drum. Typically, the wiper blades of the cleaning device are not replaceable even though they are subject to wear. Additionally, a partition is sometimes provided to help guide the falling developer particles into the chamber through the elongated aperture in the housing adjacent the chamber. The partition is normally adhered to the outer surface of the housing and extends away from the surface adjacent the elongated aperture. U.S. Pat. Nos. 4,639,123 and 4,530,594 disclose such structure.
The cleaner housing is typically rigidly mounted in the printing apparatus or rigidly mounted in a kit which is removably mounted in the main body of the printing apparatus. The wiper blade is generaly rigidly mounted relative to the drum, and because of such rigid mounting, it is necessary to precisely position the cleaner housing relative to the drum so that the proper amount of contact pressure may be applied to the drum by the wiper blade. If the blade exerts an excessive amount of pressure on the drum, the sensitive surface of the drum become scratched. On the other hand, too little pressure will fail to remove all of the developer particles from the drum.
Additionally, the construction of the housing with a lower partition ahdered thereto on its outer surface and extending along the aperture through which developer or toner paticles are collected provides a "catch all" trough along the length of the aperture in which some of the used developer particles are undesirably captured.
It is an object of the present invention to provide a cleaning device assembly for use in an image-forming apparatus.
It is a further object of the present invention to provide such a cleaning device with a wiper blade housing having a reservoir therein to collect used developer or toner particles.
It is a further object of the present invention to provide such a housing with a wiper blade assembly disposed in biased relation with the sensitive surface of a photosensitive member on an electrophotographic copying apparatus for retention of the wiper blade in contact with said sensitive surface at a predetermined contact pressure.
It is yet a further object of the present invention to provide such a housing with a lower guide member for guiding substantially all the used particles into the reservoir.
It is yet a further object of an embodiment of the present invention to provide such a cleaning device with a cleaning blade which is made of electrically conductive material for removing an electrical charge applied to the photosensitive member.
It is even yet a further object of the present invention to provide a cleaning assembly for an electrophotography apparatus, such cleaning assembly including a wiper blade having light directing paths therein for directing light to a photesensitive drum carried in the electrophotography apparatus.
A final object of the invention is to provide a cleaning assembly for an electrophotography apparatus with a wiper blade which is readily replaceable.